Why is second-order vision less efficient than first-order vision?

摘要: Abstract Research has shown that the sensitivity to second-order modulations of carrier contrast is lower than first-order luminance stimuli. We sought compare efficiency processing first- and information. Employing a phase-discrimination paradigm we found when humans were given sufficient priori information signal parameters they detected both 0.6 2 c/deg by phase-sensitive algorithm. The overall detection for patterns, however, was To study factors which limit vision, measured performance embedded in Gaussian noise. results showed patterns had sampling higher additive internal noise as compared Classification images detecting resembled side-band component suggests human observers may detect sinusoidal using channels. mechanism might be due levels those analysing patterns.